Conducting “hot work” such as welding, cutting or grinding generates heat and sparks. In certain environments hot working can be extremely hazardous, particularly where there may be combustible gases, particularly hydrocarbons, present, for example on oil/gas search and production rigs and facilities, oil refineries, chemical plants and the like.
Hot work habitats (or enclosures) permit hot work to be conducted in such environments. A hot work habitat is an enclosure which can be built around the area in which hot work is to be performed. Examples of habitats or enclosures are disclosed variously in U.S. Pat. Nos. 5,018,321, 5,101,604, 3,452,764. Once built, some habitats can be over pressurised, that is the air pressure within the habitat can be raised above the air pressure external to the habitat to prevent the ingress of potentially flammable gases into the habitat.
Conventionally, habitats are made from galvanised sheeting and wooden panelling which can be lined around the floor area with fire resistant matting. However these habitats are inflexible and cumbersome, and flexible, generally one piece, dome structures such as U.S. Pat. Nos. 5,018,321 and 5,101,604 were developed. Since then modular systems comprising flexible flame retardant fabric panels have been developed. Modular habitats have drawbacks however; firstly, in the event of a fire breaking out within the habitat, a modular habitat is not designed to contain the fire; the flame retardant fabric panels only being capable of withstanding temperatures of up to approximately 70° C. Secondly, if the fabric is breached or torn, an equalisation of pressure can result with the possible consequence of an ingress of potentially combustible gases. Such a breach can occur, for example, by performing hot work close to the flame retardant fabric such that a continual shower of sparks from grinding operations or a naked flame burns a hole in the material. The dome structures referred to above are also cumbersome to install and to fireproof adequately. A single breach in the dome renders the whole habitat unusable. Furthermore fire blankets are generally difficult to secure and install in a vertical orientation.
Whilst it would be desirable to use fireproof material instead of flame retardant fabric for the panels fireproof material is generally not suitable for stitching i.e. they cannot readily be stitched together to form panel structures or have zips or other fasteners attached thereto to allow panels to be connected together. Whilst it is possible to stitch fireproof materials specialist threads are required to maintain the fireproof integrity of the fireproof panel. It will be appreciated that any connecting means must have at least the same fireproof characteristics as the panels or the integrity thereof would be diminished in the event of a fire. One type of thread that can be used to stitch fireproof panels is a quartz based thread but such threads are generally extremely brittle and thus do not lend themselves to use in the stitching of fireproof panels for use in habitats as the constant handling of the panels would result in the thread breaking.
It is an object of at least one embodiment of the present invention to provide an improved panel for a hot working habitat.